How to Repair Water Damage to Bottom Kitchen Cabinet

Water can wreak havoc on a cabinet's outer shell, destroying the finish and blackening the wood, but that's just part of the story. It can also cause structural damage that compromises the cabinet's usefulness. This is especially true for under-sink kitchen and bathroom cabinets. You can take care of many cosmetic and structural defects yourself once things have dried out, but warping and plywood de-lamination may be severe enough to make replacement the best option.

Evaluating the Damage

The first important question that arises is whether or not the cabinet is still structurally sound. If it got wet when a pipe burst, or it's discolored by high humidity, chances are that it is. If it has sustained long-term damage from a persistent leak or high humidity, however, the glue joints may be loose and the plywood warped. The damage might be confined to the lower half of the cabinet if the drain or water valves have, unbeknown to you, been leaking. The bottom shelf may be sagging and waterlogged, and the plywood at the base of the cabinet delaminating.

Repairing Structural Damage

After you've taken care of the source of the damaging moisture and allowed the cabinet to dry out, you can repair most structural damage with some carpenter's glue, clamps and a few well-placed screws. Start by spreading the glue between delaminating layers of plywood and clamping them together with C-clamps. An examination of the inside of the cabinet may reveal weakened or separated bracing. It's usually best to knock these old braces off and reset them with new glue and screws or replace them with new ones altogether. The screws will draw the cabinet together more effectively if you've first removed the old braces.

Bleaching Out Stains

Oxalic acid effectively removes the blackening in oak and other woods caused by water penetration, but to use it, you first have to sand off the finish. Make a saturated solution of oxalic acid crystals and water -- that's a solution in which no more crystals will dissolve -- and brush it onto the affected wood. You should notice an improvement when it dries, but if not, brush more. When you're done, dissolve 1/2 cup of baking soda in a gallon of water and sponge it on the wood to neutralize the acid, then wash the area with clear water. When the wood dries, it's ready for refinishing.

Replacing Parts

You may find that there's no alternative to replacing some part of the cabinet. For example, when the bottom shelf becomes so waterlogged that it sags, it's time for a new one. Depending on the cabinet design, you may not be able to extract it in one piece, so be sure to get its exact dimensions before demolishing it. If the veneer has separated from the side or front of the cabinet, you may be able to re-skin it by gluing on a new veneer with contact cement as an alternative to replacing it. Just be sure to cut off as much of the old veneer as possible first.

How to Repair Water Damage to Bottom Kitchen Cabinet

Source: https://homeguides.sfgate.com/repair-waterdamaged-cabinet-87469.html